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  1. #1
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    Good job! First good set of hills on new Powertap...

    This thing is awesome. Nice to have the immediate feedback for motivation.

    Anyway, did an indoor test to calculate FTP and came up with 255 watts...about what I figured. This was really a strain and had an avg HR of 177, I hate riding indoors. Went out and did 5x9 min. L4 (230-270 watts) repeats with 4 min. recovery on a hill nearby my house today. Felt much better putting out the power being outside.

    Avg power for all 5 intervals was 272 watts! Better than I was shooting for, stoked on this. HR was avg 169 for all of them and constant over the last 5 minutes of each interval.

    QUESTIONS-

    1) Does this power level for these intervals seem in line with the zone? I was targeting 250w to be right in the middle of the zone and overshot it.

    2)I feel like I had some juice still in the legs while doing this. Do I need to retest my FTP outdoors?

    3)Has anyone tested indoors and out and gotten a noticeable discrepancy?

    I know there are some wattage geeks out there that love all this stuff. Thoughts?

  2. #2
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    As far as Zones, I typically will try to do my sets at the highest overall average. On sets of 3 or more, I will hold back a bit on the first to find the feel, and work a little harder with hopes of finishing the last rep close to my best. Some days are better than others, and I'll take the better numbers if the legs want to deliver. I just try to keep it controlled enough that I can finish the set without fading too much.

    I will always put out better power on climbs, and definitely see better numbers outdoors.

    As far as your FTP, you might adjust it up some, try 260. But over time you will continue to get a better feel for what "threshold" feels like. FTP changes a bit with every day depending on the day, the meter, and the terrain. You don't have to be exact, I will always use PE (perceived exertion) to find the right intensity for the workout. If I am totally missing the mark or overshooting, then FTP might need adjusting... but rather than try to figure it out I will chalk it up as great legs, or maybe a bit tired, or whatever and adjust the interval intensity based on PE. If over time I see a 5% or better trend (up or down) I might consider an FTP test or just go ahead and adjust the number.

    I haven't formally tested my FTP since 2008. My FTP changes a bit throughout the season, but rather than rest up and get a "fresh legs" test, I just use PE to fine tune the interval intensity. I save the "fresh legs" for events. For me the best indicator of FTP is 2x20min threshold intervals.The 2nd interval is usually pretty close (if I'm training and not to fresh), and its a great training session. Shorter intervals give me a clue (like 10min), but depending on fitness and freshness I may be able to avg 5% better than FTP.

    20min and shorter durations are largely impacted by a riders Anaerobic Capacity. Some riders will do well above FTP on shorter (sustained) durations, and some riders will be closer to FTP. After accumulating plenty of files with a variety of different interval durations you will see the trends. Cool stuff, congrats on the new meter

  3. #3
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    What test did you do to come up with a 255 watt FTP? A avg HR of 177 sounds pretty high for a threshold HR.
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  4. #4
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    20 min test x .95 for FTP of 255 watts. 20 min. was 275 watt average.

  5. #5
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    Quote Originally Posted by XCFred
    What test did you do to come up with a 255 watt FTP? A avg HR of 177 sounds pretty high for a threshold HR.
    Huh?

    If he has a max of 200bpm, that's not even 90%. I know I certainly operate well above 177bpm; no reason plenty of other people can't as well.

  6. #6
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    I ride with a powertap on my road bike, but in answer to some of your questions:

    I have not been able to produce the same power on an indoor trainer as I can outside, with a very big difference (10%-15%). I do have a set of rollers now, with a headwind fan, and think my power is closer to outdoor power with the rollers but I haven't tried an FTP test on the rollers and probably won't do so. If I were you I'd do the testing outdoors to get the right zones set up for outdoor riding.

    In terms of targeting wattage during an interval, the power jumps around so much due to hills, wind, grade of road, etc. that it will take you a while to learn to ride at a certain power level. You'll get better over time and "know" what 250 feels like--so even though the power on the meter is jumping around you can do a pretty good job of keeping power in your planned range. I would imagine if you've got the powertap on your mountain bike that the fluctations are even more significant.

    Congrats on getting a power meter. I've had one since Christmas, had a few months where I couldn't train well, then have gotten into a rythm lately and done a lot of road riding. I got back on the mtb some this past week, did my ole' standard time trial course, and crushed my previous PR (I had been at a plateau for a while and was stoked to have broken through big time). My volume was actually less than when I was training well last year, so I attribute a lot of the fitness improvement to the power meter.

  7. #7
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    Yeah, 10 to 15 percent seems accurate. HR and power are similar to outside...that PE is just 1 or 2 higher.

  8. #8
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    Quote Originally Posted by Johnny K
    This thing is awesome. Nice to have the immediate feedback for motivation.

    Anyway, did an indoor test to calculate FTP and came up with 255 watts...about what I figured. This was really a strain and had an avg HR of 177, I hate riding indoors. Went out and did 5x9 min. L4 (230-270 watts) repeats with 4 min. recovery on a hill nearby my house today. Felt much better putting out the power being outside.

    Avg power for all 5 intervals was 272 watts! Better than I was shooting for, stoked on this. HR was avg 169 for all of them and constant over the last 5 minutes of each interval.

    QUESTIONS-

    1) Does this power level for these intervals seem in line with the zone? I was targeting 250w to be right in the middle of the zone and overshot it.

    2)I feel like I had some juice still in the legs while doing this. Do I need to retest my FTP outdoors?

    3)Has anyone tested indoors and out and gotten a noticeable discrepancy?

    I know there are some wattage geeks out there that love all this stuff. Thoughts?
    You should test your power outdoors, with a 20 minute Field Test. Indoor efforts are going to be lower almost always, for the same efforts indoors, perceived exertion indoors will always be much higher, due to the lack of movement. If you're training outdoors, set your FTP outdoors. You can reset it in the winter on the trainer when you'll do your training indoors..

    #1 Re test your zones, then review your individual efforts. Was the first effort at 290? the second 280, 3rd 270, 4th 260?? etc, look for trends in the power. You want to 'flat-top' your efforts, so that the last one is just as good as your first one.

    You should have some juice left in the legs after 36 minutes of threshold. By definition threshold is an hour's worth of efforts, but that's not the goal. The goal of a workout like this is to stay consistent and constant and get in 4 hard efforts at threshold to force adaptation. You'll be tired, but it shouldn't be FULL GAS (sprints or Vo2 efforts where you are slumped over the bars at the end)

  9. #9
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    Quote Originally Posted by Johnny K
    20 min test x .95 for FTP of 255 watts. 20 min. was 275 watt average.
    The 20 min x .95 is a web forum perversion of the test protocol from the Hunter Allen book. If I recall correct, the actual test in the book is preceded by an all out 5 minute effort, a few all out 1 minute efforts, THEN you do the 20 minute test and multiply the result by 0.95. Just multiplying the result of a 20 minute test by 0.95 will result in an overestimate of FTP unless you are an endurance freak who's been training for years and has little to no anaerobic capacity.

  10. #10
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    Quote Originally Posted by strader
    The 20 min x .95 is a web forum perversion of the test protocol from the Hunter Allen book. If I recall correct, the actual test in the book is preceded by an all out 5 minute effort, a few all out 1 minute efforts, THEN you do the 20 minute test and multiply the result by 0.95. Just multiplying the result of a 20 minute test by 0.95 will result in an overestimate of FTP unless you are an endurance freak who's been training for years and has little to no anaerobic capacity.

    That is true.

  11. #11
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    Quote Originally Posted by Poncharelli
    That is true.
    Ponch, you or anyone else have a good link for the proper protocol for doing a 20 minute field test. I never knew there were any pre efforts so to say...

  12. #12
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    My personal preference for an easy, quick way to get a reasonably close estimate of FTP is to use the Monod Critical power calculation protocol with one 20 min tt and one 5 min tt (or something similar like a 12 min and a 3 min--but the shorter you go, the less accuracy you'll probably have). I have a spreadsheet that I use to easily calculate estimated FTP with the Monod calculation--slope of the line between two plotted points (see description below). It's pretty easy to create a simple spreadsheet that will calculate the slope from your two efforts.

    Here's a great link to a page describing various ways to estimate FTP:
    http://home.trainingpeaks.com/articl...old-power.aspx

    From that linked page, here's a description of the Monod method:
    "5.Finally, those who are more mathematically inclined may wish to perform formal testing to determine their "critical power" as described in the scientific literature. Briefly, this approach consists of plotting the total work performed (in joules) during a series of relatively short (i.e., between 3 and perhaps 30 min), all-out efforts against their duration (in seconds), then fitting a straight line to the data points. The slope of this line is critical power, which corresponds quite closely with functional threshold power determined using any of the previously-described methods."
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  13. #13
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    Quote Originally Posted by Johnny K
    Ponch, you or anyone else have a good link for the proper protocol for doing a 20 minute field test. I never knew there were any pre efforts so to say...
    Here's a good method, per Joe Friel's blog:

    "There are many ways to find your FTP. My favorite is simply to have the athlete complete an all-out, solo 30-minute time trial which is NOT part of a race. I've found the average power for this 30-minute, solo effort to be quite close to what the athlete does in a 60-minute race, such as a 40k time trial. The reason is that when riding alone you'll feel sorry for yourself and not go as hard as you would should it be a 30-minute race where you are held accountable to the world for your results and motivation is therefore considerably higher."



    In road racing, I find it real interesting. I race a lot of Masters Cat 4's road races, and a lot of the guys train with power. It's interesting hearing how different our power outputs are and our relative race performance. There are some correlations, but not really.

    Of course, the guys with the highest FTP do best in flat TT's. But FTP really fails to measure how quickly one recovers from short-hard efforts, reproducing power after short hard efforts, and power deteriotation over long periods. Pretty HUGE factors in race performance, IMO.

  14. #14
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    Quote Originally Posted by millennium
    My personal preference for an easy, quick way to get a reasonably close estimate of FTP is to use the Monod Critical power calculation protocol"
    I have found the Monod predictions to be accurate for my own numbers. I use a 3min, 8min and 20min. It spit out a 60min prediction that seemed a little high, but in race files I have seen NP's real close to what Monod predicted. Kinda creepy how predictable we are, and also kinda creepy how NP and Monod believed I could do better than I thought.

    I dread all-out efforts, too old for that stuff. But in group rides and races I often see various durations with surprising averages, and it works pretty good to plug those into Monod and see the result.. it's pretty close for sure, definitely as close as anything else.

    Also, I have trouble getting motivated to go out and bury myself when the only thing on the line is a number. I'd rather use interval performance and pieces of random performances to verify that my FTP setting is close. In the end its not critical that FTP be exactly predicted, its a moving target anyway. As long as its close, the zones will be good, performance manager will be good, and I can save those "all outs" for the days when I feel good or when its the big race and everything is going to plan.. (which doesn't happen much!).

  15. #15
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    Quote Originally Posted by millennium
    From that linked page, here's a description of the Monod method:
    "5.Finally, those who are more mathematically inclined may wish to perform formal testing to determine their "critical power" as described in the scientific literature. Briefly, this approach consists of plotting the total work performed (in joules) during a series of relatively short (i.e., between 3 and perhaps 30 min), all-out efforts against their duration (in seconds), then fitting a straight line to the data points. The slope of this line is critical power, which corresponds quite closely with functional threshold power determined using any of the previously-described methods."
    So roughly like this:

    3 min = X Joules
    20 min = Z Joules

    Slope = (Z-X)/(20-3) = (Z-X)/17


    If using more data points, one can use Excel for best fit line. Right?

  16. #16
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    Quote Originally Posted by Poncharelli
    So roughly like this:

    3 min = X Joules
    20 min = Z Joules

    Slope = (Z-X)/(20-3) = (Z-X)/17


    If using more data points, one can use Excel for best fit line. Right?

    You don't use minutes--rather, you use seconds.

    I'm going to try and attach a zip file to this post that contains my simple Monod Critical Power Calculation spreadsheet. Let me know if you can download and use it. It only has option to insert two data points--but you could easily add three or more and then adjust the slope formula to use all of the data. The yellow boxes are where you insert your watts and the corresponding seconds. The other boxes calculate automatically.
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  17. #17
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    Quote Originally Posted by perryr
    But in group rides and races I often see various durations with surprising averages, and it works pretty good to plug those into Monod and see the result.. it's pretty close for sure, definitely as close as anything else.
    I often do the same thing (i.e. plug in my recent best avg power from hard rides and races for various shorter durations up to 20 mins). I especially do it when I just want a quick check on FTP if I suspect a change in FTP. This seems to give pretty good FTP estimate for me too.
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  18. #18
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    Quote Originally Posted by XCFred
    What test did you do to come up with a 255 watt FTP? A avg HR of 177 sounds pretty high for a threshold HR.
    my threshold is 176bpm

  19. #19
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    Quote Originally Posted by XCFred
    What test did you do to come up with a 255 watt FTP? A avg HR of 177 sounds pretty high for a threshold HR.
    Hardly. I used to race crits with a HRavg of 183, HRmax being 189. FTP back then was 305.

    Currently I'm in nowhere near the same form as I was back then - last night for example was a HRavg of 170 with an average power of 225 (figures are down because it was muddy as hell), current FTP is 260. Current FTHR is 178.

    The point of this story? Everyone's physiology is different, even down to how well trained they are at present.


    A lot of what you can do is also about hormones. I know that if I go out and hit one of the local hills on my own, I'll top out around 270 for any sustained period. But if I'm on the front of a bunch down Beach Road, or racing a crit, I'll have no issues at all sitting on that same wattage. My HR will be significantly higher, usually at least 10-20bpm higher, and I'll still feel like I'm just cruising along comfortably.
    Out on my own I struggle to push my HR beyond about 170. In a crit, I'm lucky if it falls below. In a proper race? It'll be up and down all over the place.
    I know that personally, I can push both my HR and power much higher on the trainer than outside on the roads.
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  20. #20
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    Should I be including zeros in the avg power calcs on my Powertap in setup mode? I set it u p that way, not sure if it matters much.

  21. #21
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    Quote Originally Posted by Johnny K
    Should I be including zeros in the avg power calcs on my Powertap in setup mode? I set it u p that way, not sure if it matters much.
    I include zeroes on the head unit's avg power calcs. But, for FTP testing (3mins, 10mins, 20mins or whatever the length of your TT), you shouldn't have any zeros because you should be constantly pedaling with resistance. So, for FTP testing, it shouldn't matter whether or not your head unit is set to include zeroes in the head unit's avg power calcs.
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  22. #22
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    Here is the protocol according to the book:

    Warm up, 15 mins with 3 1 minute intervals of high cadence (>100)

    Then, all out for 5 mins

    Then 10 mins recovery

    Then 20 mins FTP test

    15 mins warm down

  23. #23
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    IMO the 20 minute tests are really poor at determining this - i've seen anywhere from 91% to 98% of the 20 min test equals FTP. Just taking 95% will get you in the ballpark but you'll quickly find out if its too high or too low when you start trying to hit wattage targets on interval workouts!

    My prefererce for testing is to do a hillclimb that takes about 45 mintes ... not quite a full hour test. FTP is the power you can hold for 60 minutes given the perfect conditions (well rested, perfect nutrition, highly motivated, etc). So I figure that with residual fatigue and the fact that its just a solo training ride, my wattage for 45 min will be pretty close to my FTP.

    FWIW, I also use the Monod calcs to determine FTP and come up with almost identical numbers. The other method I like is to look over past data for my maximum normalized power for 60 minutes.

    That is how FTP estimation generally works, there are so many different methods that eventually, as you gather more and more data, you find a few methods that converge on a certain number.

  24. #24
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    There isn't a hill that'd take 45 minutes to climb in my whole state! There's also nothing flat. I was thinking about doing the state time trial championships just to measure power for 60+ minutes since I seem to do better when I've got a carrot to chase.

  25. #25
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    Quote Originally Posted by Poncharelli
    Here's a good method, per Joe Friel's blog:

    "There are many ways to find your FTP. My favorite is simply to have the athlete complete an all-out, solo 30-minute time trial which is NOT part of a race. I've found the average power for this 30-minute, solo effort to be quite close to what the athlete does in a 60-minute race, such as a 40k time trial. The reason is that when riding alone you'll feel sorry for yourself and not go as hard as you would should it be a 30-minute race where you are held accountable to the world for your results and motivation is therefore considerably higher."



    In road racing, I find it real interesting. I race a lot of Masters Cat 4's road races, and a lot of the guys train with power. It's interesting hearing how different our power outputs are and our relative race performance. There are some correlations, but not really.

    Of course, the guys with the highest FTP do best in flat TT's. But FTP really fails to measure how quickly one recovers from short-hard efforts, reproducing power after short hard efforts, and power deteriotation over long periods. Pretty HUGE factors in race performance, IMO.
    Ok, just tried this method...hurts but effective. 265 watt average for 30 minutes and 171 avg HR for a 65 kg rider.

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